Journal of Geodetic Science最新文献_第5页

The ambiguous sea level rise at Brest’s 212 yearlong record elucidated 布雷斯特长达212年的海平面上升记录得到了阐明

IF 1.3

Journal of Geodetic Science Pub Date : 2021-01-01 DOI: 10.1515/jogs-2020-0124

H. Iz, C. Shum

{"title":"The ambiguous sea level rise at Brest’s 212 yearlong record elucidated","authors":"H. Iz, C. Shum","doi":"10.1515/jogs-2020-0124","DOIUrl":"https://doi.org/10.1515/jogs-2020-0124","url":null,"abstract":"Abstract The tide gauge record at Brest, France, along Eastern part of Atlantic coast is one of the longest records in Europe spanning 212 years (1807–2019). Analyzing these records has important ramifications in assessing anthropogenic impact of climate change at local and regional scales during this period. All the previous studies that analyzed Brest’s tide gauge record have used vaguely defined quadratics models and did not incorporate the effect of sea level variations at various frequencies, which confounded the presence or absence of a plausible uniform acceleration. Here, we entertained two competing kinematic models; one with a uniform acceleration representing 212 years of monthly averaged tide gauge data, the other is a two-phase trend model (Phase I is 93 years long and Phase II is 119 years long). Both models include statistically significant (α = 0.05) common periodic effects, and sub and super harmonics of luni-solar origin for representing monthly averaged sea level anomalies observed at Brest. The least squares statistics for both models’ solutions cannot distinguish one model over the other, like earlier studies. However, the assessment of Phase I segment of the records disclosed the absence of a statistically significant trend and a uniform acceleration during this period. This outcome eliminates conclusively the occurrence of a uniform acceleration during the entire 212-year data span of the tide gauge record at Brest, favoring the two-phase trend model as a sound alternative.","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80124804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Comparative analysis of blind tropospheric correction models in Ghana 加纳对流层盲校正模式的对比分析

IF 1.3

Journal of Geodetic Science Pub Date : 2021-01-01 DOI: 10.1515/jogs-2020-0104

S. Osah, Akwasi Acheampong, C. Fosu, I. Dadzie

{"title":"Comparative analysis of blind tropospheric correction models in Ghana","authors":"S. Osah, Akwasi Acheampong, C. Fosu, I. Dadzie","doi":"10.1515/jogs-2020-0104","DOIUrl":"https://doi.org/10.1515/jogs-2020-0104","url":null,"abstract":"Abstract The impact of the earth’s atmospheric layers, particularly the troposphere on Global Navigation satellite system (GNSS) signals has become a major concern in GNSS accurate positioning, navigation, surveillance and timing applications. For precise GNSS applications, tropospheric delay has to be mitigated as accurately as possible using tropospheric delay prediction models. However, the choice of a particular prediction model can signifi-cantly impair the positioning accuracy particularly when the model does not suit the user’s environment. A performance assessment of these prediction models for a suitable one is very important. In this paper, an assessment study of the performances of five blind tropospheric delay prediction models, the UNB3m, EGNOS, GTrop, GPT2w and GPT3 models was conducted in Ghana over six selected Continuously Operating Reference Stations (CORS) using the 1˚x1˚ gridded Vienna Mapping Function 3 (VMF3) zenith tropospheric delay (ZTD) product as a reference. The gridded VMF3-ZTD which is generated for every six hours on the 1˚x1˚ grids was bilinearly interpolated both space and time and transferred from the grid heights to the respective heights of the CORS locations. The results show that the GPT3 model performed better in estimating the ZTD with an overall mean (bias: 2.05 cm; RMS: 2.53 cm), followed by GPT2w model (bias: 2.32cm; RMS: 2.76cm) and GTrop model (bias: 2.41cm; 2.82cm). UNB3m model (bias: 6.23 cm; RMS: 6.43 cm) and EGNOS model (bias: 6.70 cm; RMS: 6.89 cm) performed poorly. A multiple comparison test (MCT) was further performed on the RMSE of each model to check if there is significant difference at 5% significant level. The results show that the GPT3, GPT2w and GTrop models are significantly indifferent at 5% significance level indicating that either of these models can be employed to mitigate the ZTD in the study area, nevertheless, the choice of GPT3 model will be more preferable.","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75926081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Arne Bjerhammar- a personal summary of his academic deeds Arne Bjerhammar——对他学术成就的个人总结

IF 1.3

Journal of Geodetic Science Pub Date : 2021-01-01 DOI: 10.1515/jogs-2020-0117

L. Sjöberg

引用次数: 1

Editorial to the Special Issue on the International Symposium on Applied Geoinformatics 2019 2019年应用地理信息学国际研讨会特刊社论

IF 1.3

Journal of Geodetic Science Pub Date : 2021-01-01 DOI: 10.1515/jogs-2020-0119

J. Paziewski, D. U. Sanli

{"title":"Editorial to the Special Issue on the International Symposium on Applied Geoinformatics 2019","authors":"J. Paziewski, D. U. Sanli","doi":"10.1515/jogs-2020-0119","DOIUrl":"https://doi.org/10.1515/jogs-2020-0119","url":null,"abstract":"Over the last years, we have observed signi cant technological developments in both instrumentation and algorithms aiming at capturing and processing geodetic and geospatial data. As a result currently most of the information about the Earth’s shape and surface is retrieved with the use or with augmentation of satellite-based systems. With such cutting-edge advances, it is now feasible to meet high requirements of conventional geodetic and surveying applications. Considering the GNSS technology as an example, it is possible to determine the positionwith a degree of precision that was previously unachievable by traditional surveying methods. But more importantly, these developments stimulate a broad range of new applications, the creation of novel opportunities and themarket for geodetic techniques. In this respect the International Symposium onApplied Geoinformatics (ISAG) 2019 has naturally become a crucial waypoint on the map of geodetic conferences and seminars. This symposium aimed to provide an international forum for the exchange of ideas and the creation of knowledge for the recent advances on various aspects of theories and applications of geodesy and geoinformatics. This Special Issue in the Journal of Geodetic Science gathers ve peer-reviewed papers that advance the state-of-the-art andoriginate from the International SymposiumonApplied Geoinformatics held at the Yildiz Technical University in Istanbul from 7 to 9 November, 2019. Several studies contained in this Special Issue of the Journal of Geodetic Science are related to the advances in the theory of geodetic observation adjustment. Duchnowski and Wyszkowska (2020) deal with testing the normality of selected variants of theHodges-Lehmann estimators. With the analyses based on the Monte Carlo method and Jarque–Bera test, the authors proved the normality of Hodges-Lehmann estimators. As shown by the authors,","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78944631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Kinematic GNSS positioning results compared against Agisoft Metashape and Pix4dmapper results produced in the San Joaquin experimental range in Fresno County, California 运动学GNSS定位结果与Agisoft Metashape和Pix4dmapper在加利福尼亚州弗雷斯诺县圣华金实验范围内产生的结果进行了比较

IF 1.3

Journal of Geodetic Science Pub Date : 2021-01-01 DOI: 10.1515/jogs-2020-0122

M. Berber, R. Munjy, J. Lopez

{"title":"Kinematic GNSS positioning results compared against Agisoft Metashape and Pix4dmapper results produced in the San Joaquin experimental range in Fresno County, California","authors":"M. Berber, R. Munjy, J. Lopez","doi":"10.1515/jogs-2020-0122","DOIUrl":"https://doi.org/10.1515/jogs-2020-0122","url":null,"abstract":"Abstract RTKLIB which is an open source Global Navigation Satellite Systems (GNSS) software has gained rapid acceptance among Surveying professionals thanks to recent developments in UAS (Unmanned Aerial System) technology. RTKLIB enables standard and precise point positioning (PPP) in real-time and post-processing modes to be performed. As such, UAS users utilize this software to analyze GNSS data collected by GNSS systems on UAS. By being versatile and free, RTKLIB is commonly used by many; however, it is not the only freely available GNSS software. There are also freely available online GNSS data processing software running on servers. These online GNSS data processing services provide data processing in static, kinematic and rapid static modes. Because UAS collect data in kinematic mode, in this study, kinematic data processing by aforementioned software (CSRS-PPP, GAPS and APPS) is analyzed. The results coming from these software are compared against the results produced by photogrammetric software (Agisoft Metashape and Pix4Dmapper). The aim of this practical project is to produce generalizable knowledge about the performance of these software. It is found out that RTKLIB and CSRS-PPP achieved cm-level precision. Yet, GAPS and APPS achieved dm-level precision both for horizontal and vertical coordinates. This study demonstrates the precision and accuracy expected from these software if they are used for kinematic GNSS data processing.","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74589986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Coastal marine gravity modelling from satellite altimetry – case study in the Mediterranean 基于卫星测高的沿海海洋重力模拟——地中海的案例研究

IF 1.3

Journal of Geodetic Science Pub Date : 2021-01-01 DOI: 10.1515/jogs-2020-0200

A. Abulaitijiang, O. Andersen, R. Barzaghi, P. Knudsen

引用次数: 1

ROTI maps of Greenland using kriging 使用克里格绘制的格陵兰岛ROTI地图

IF 1.3

Journal of Geodetic Science Pub Date : 2021-01-01 DOI: 10.1515/jogs-2020-0123

S. Beeck, A. Jensen

{"title":"ROTI maps of Greenland using kriging","authors":"S. Beeck, A. Jensen","doi":"10.1515/jogs-2020-0123","DOIUrl":"https://doi.org/10.1515/jogs-2020-0123","url":null,"abstract":"Abstract GNSS satellite signals are affected by the media when traversing Earth’s atmosphere, and the performance of GNSS based positioning and navigation is correlated with these effects. In the ionosphere, the signals are affected by the number of electrons along the signal path which can be quantified by the total electron content. The focus of this article is scintillation effects caused by electrons in the Arctic ionosphere, and the rate of the total electron content index, the ROTI, is used as a measure of the scintillation. Data from permanent GNSS reference stations in Greenland is used to generate maps of the ROTI in Greenland, and the novelty of the work in this paper is the application of the ordinary kriging method as the basis for ROTI maps in the Arctic. Further, the choice of satellite constellations as well as the elevation mask used in the data analyses are analyzed and discussed. Also, the performance of using ordinary kriging for ROTI maps during times with both a low and a very high geomagnetic activity are discussed. The results show that ordinary kriging performs well during high geomagnetic activity, while during low activity the natural neighbor interpolation method is a better choice for the Arctic.","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76041049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Accurate Sea Surface heights from Sentinel-3A and Jason-3 retrackers by incorporating High-Resolution Marine Geoid and Hydrodynamic Models 通过结合高分辨率海洋大地水准面和水动力模型，从Sentinel-3A和Jason-3跟踪器获得精确的海面高度

IF 1.3

Journal of Geodetic Science Pub Date : 2021-01-01 DOI: 10.1515/jogs-2020-0120

M. Mostafavi, N. Delpeche-Ellmann, A. Ellmann

{"title":"Accurate Sea Surface heights from Sentinel-3A and Jason-3 retrackers by incorporating High-Resolution Marine Geoid and Hydrodynamic Models","authors":"M. Mostafavi, N. Delpeche-Ellmann, A. Ellmann","doi":"10.1515/jogs-2020-0120","DOIUrl":"https://doi.org/10.1515/jogs-2020-0120","url":null,"abstract":"Abstract One of the major challenges of satellite altimetry (SA) is to produce accurate sea surface heights data up to the shoreline, especially in geomorphologically complex sea areas. New advanced re-tracking methods are expected to deliver better results. This study examines the achievable accuracy of Sentinel-3A (S3A) and Jason-3 (JA3) standard retrackers (Ocean and MLE4) with that of improved retrackers adapted for coastal and sea ice conditions (ALES+ SAR for S3A and ALES+ for JA3). The validation of SA data was performed by the integration of tide gauges, hydrodynamic model and high-resolution geoid model. The geoid being a key component that links the vertical reference datum of the SA with other utilized sources. The method is tested in the eastern section of Baltic Sea. The results indicate that on average reliable sea surface height (SSH) data can be obtained 2–3 km from the coastline for S3A (for both Ocean and ALES+SAR) whilst an average distance of 7–10 km for JA3 (MLE4 and ALES+) with a minimum distance of 3–4 km. In terms of accuracy, the RMSE (with respect to a corrected hydrodynamic model) of S3A ALES+ SAR and Ocean retrackers based SSH were 4–5 cm respectively, whereas with the JA3 ALES+ and MLE4 associated SSH RMSE of 6–7 cm can be achieved. The ALES+ and ALES+ SAR retrackers show SSH improvement within a range of 0.5–1 cm compared to the standard retrackers. This assessment showed that the adaptation of localized retrackers for the Baltic Sea (ALES+ and ALES+SAR) produced more valid observation closer to the coast than the standard retrackers and also improved the accuracy of SSH data.","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85669301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Positional uncertainty of network RTK observations in a modern datum 现代基准下网络RTK观测的位置不确定性

IF 1.3

Journal of Geodetic Science Pub Date : 2021-01-01 DOI: 10.1515/jogs-2020-0116

T. Bernstein, V. Janssen

{"title":"Positional uncertainty of network RTK observations in a modern datum","authors":"T. Bernstein, V. Janssen","doi":"10.1515/jogs-2020-0116","DOIUrl":"https://doi.org/10.1515/jogs-2020-0116","url":null,"abstract":"Abstract The Geocentric Datum of Australia 2020 (GDA2020) is Australia’s new and much improved national datum. It is based on a single, nationwide least squares network adjustment that rigorously propagates uncertainty. This paper explores three options to include Network Real-Time Kinematic (NRTK) observations and their Positional Uncertainty (PU) in the survey control network of New South Wales (NSW) via the GDA2020 state adjustment. In the first option, PU is empirically estimated based on a dataset of more than 1,500 observations to obtain values that can be uniformly applied to all NRTK observations. In the second option, PU is calculated for each NRTK observation, based on the coordinate quality indicators provided by the Global Navigation Satellite System (GNSS) equipment. Both options continue to treat NRTK observations as point-based position solutions, resulting in poor correlation with surrounding survey control marks. The third option overcomes this issue by utilising the automatically computed GNSS baselines between NRTK observations and their Virtual Reference Station (VRS) to create a connected network that can be adjusted like a static GNSS network. Using a typical urban NRTK survey in Sydney as an example, it is shown that this method offers a rigorous computation of PU, while maintaining the quick and easy nature of NRTK positioning.","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75188460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Analytical and numerical methods of converting Cartesian to ellipsoidal coordinates 将笛卡尔坐标转换为椭球坐标的解析和数值方法

IF 1.3

Journal of Geodetic Science Pub Date : 2021-01-01 DOI: 10.1515/jogs-2020-0126

G. Panou, R. Korakitis

引用次数: 4